Yesterday’s news included three informative pieces on ethanol subsidies and why they endure. First, New Scientist reports on yet another study showing that ethanol and similar biofuels do not reduce the amount CO2 in the atmosphere:

Righelato and Dominick Spracklen of the University of Leeds, UK, calculated how long it would take to compensate for those initial emissions by burning biofuel instead of gasoline. The answer is between 50 and 100 years. “We cannot afford that, in terms of climate change,” says Righelato.

The researchers also compared how much carbon would be stored by replanting forests with how much is saved by burning biofuel grown on the land instead of gasoline.

They found that reforestation would sequester between two and nine times as much carbon over 30 years than would be saved by burning biofuels instead of gasoline (see bar chart, right). “You get far more carbon sequestered by planting forests than you avoid emissions by producing biofuels on the same land,” says Righelato.

He and Spracklen conclude that if the point of biofuels policies is to limit global warming, “policy makers may be better advised in the short term to focus on increasing the efficiency of fossil fuel use, to conserve existing forests and savannahs, and to restore natural forest and grassland habitats on cropland that is not needed for food.”

So why do the subsidies keep coming? Because they’re good politics! If you want to win Iowa, you’ve got to like ethanol :

Three Republican presidential candidates, former Massachusetts Gov. Mitt Romney, former New York Mayor Rudy Giuliani and former Arkansas Gov. Mike Huckabee, all visited the Iowa Falls refinery, where they pledged further investment in alternative energy.

Over the past year, two other candidates, Sen. Hillary Rodham Clinton (D-N.Y.) and Sen. John McCain (R-Ariz.), went from strongly opposing the expansion of ethanol to endorsing it.

Backing ethanol is a political necessity in the state that is the traditionally the first to choose its presidential candidates. Iowa boasts the greatest number of ethanol plants in the country, producing about 30 percent of the U.S. supply. Ethanol is Iowa’s golden, corn-fed goose.

And it’s not just for corn. With cheaper sugar imports soon to arrive from Mexico, American growers used to protective quotas are looking to ethanol as a way to keep prices up:

Under the farm bill the House passed last month, the federal government would buy surplus sugar and sell it to ethanol producers, where it would be used in a mixture with corn. The program was inserted as a hedge against a looming North American Free Trade Agreement provision, which will let Mexico export unlimited amounts of sugar to the U.S. starting next year…

The chairman of the House Agriculture Committee, Minnesota Democrat Collin Peterson, inserted the sugar-to-ethanol provision in the farm bill. Minnesota is the nation’s largest producer of sugar beets, and Peterson represents the state’s sugar beet-growing Red River Valley. U.S. sugar is made from beets in some Northern and Western states, and cane in a few Southern states and Hawaii.

The media writes about ethanol as if it’s part of energy policy. That’s just a pretense. It’s farm policy.